Ideal pressures etc...

[funzrlow]

Please, I need some help. I just graduated from Apex Tech in the city. All throughout school, instructors told me how after school I would get some job as an apprentice and work under a mechanic who would show me the ropes. I felt comfort in this notion. I just got hired by a company of "restauranteurs" in the city. These guys own 8 restaraunts in Manhattan. They hired me to be their Refrigeration Technician. They offered me above and beyond what I ever expected to get just after school despite the fact that I told them that I really had minimal field experience.
Here is my issue. I have never had any experience with Icemakers or walk-in type refrigerators. I have had very little experience with low-boys or any other type of commercial application for that matter.
Today was my first day... The new Boss (not in the ref. field) tells me to go check pressures on the units to see if they are operating properly.
I really have no idea what optimum pressures would be.
I'm not even positive of what refrigerant is in these systems.
Bottom line... if there is anyone with some type of helpful info that may keep me from getting fired from my first job out of school, it would be greatly appreciated.

[hoozdis]

...your bass has no experience then he doesnt even know what he is looking for, secondly, if you check the temperature on the walk ins etc. and they are coolong correctly then theres no reason to touch them. If they have a perfect charge, they will not have such after you put gages on them

[frozensolid]

You mean in school, they did not ever teach you how to read a pressure temperature chart.

Get one and learn to read it. Then keep your coil at least 10 degrees colder than your box.

With schools like that, you would be better off if you just read this entire web site. Here, you can learn.

[funzrlow]

Thanx for the tips...keep 'em coming...please. I'm sorry, I didn't mean to make it sound like they didn't teach us how to use a P/T chart, they most definately did. Apex just simply did not give us adequate Shop time (i.e. hands on training).
Thanx for any helpful info any of you may send my way.

[cobitech]

funzrlow,

Just remember the 10-20-30 method.
10 for low temp.
20 for medium temp.
30 for High temp.

just say that you are using 404-a for instance and you want a -10° box temp,subtract 10 from that and you will have a -20° evaporator coil.
which is 16 Psig on your P.T. chart. get it...
and it applies to most all refrigerant types.

It's the way I remember to charge units and it works.,

[R12rules]

Contact me via my profile. I will give you my cell phone number which you can call during the day and I will walk you thru your adventure, step by step.

If you visit my website, you will find my number there also. Simply phone me, if you wish.

[R12rules]

Get busy reading this site.

Post questions OFTEN! Seriously!

Read thru Tips & Tricks of The Trade. read it all!!!

The go looking for more adivce.

Read thru past stuff under Refrig & Ice Making. Go all the waaaayyyy back ... each and every page .... read the stuff that you believe will help you the most ... at first.


What do you have for tools, a vehicle, test equipment, etc. ???

Do yo have open accounts anywhere? Are they giving you a checking account to draw off of? A credit card maybe?


Try and stay away from all plumbing work, especially any thing to do involving drains. Drain lines. Drain cleaning. Drain inspections. Drain pipes. Or "Fudge Packing".

[Edited by R12rules on 05-24-2004 at 10:34 PM]

[s tek]

Most of us have been in that stage, whether we admit it or not is another story. If nothing is wrong write down the pressures and line temp on each unit note the superheat & subcool and when something happens you can go back to the previous reading and have an idea what is going on. Go back to your books and find that chart that has all the arrows on it and copy it and carry it with you. If you have a problem post all the info you can get on here and some of us will help, others will harass but pay no attention to them.

[gbfromsd]

Oh my god, absolutely positively a tough road to hoe.
You can do A/C and be half good, but reefers are picky as
heck - and freezers have to be just right.

You can figure the book stuff I reckon. PT charts and
gases, but you better be asking some questions. There's
just a ton of 'little' things you're gonna need.

Best wishes to ya and do post often.

[funzrlow]

I just wanted to take a minute and tell you fellas that I really appreciate all of the replies. My second day (today) on the job was not as gut wrenching as the first day. I spent most of the day cleaning condenser coils and registers and all that good stuff.
I went to one of the larger restaurants (quite possibly the largest that they own) and decided to take an inventory of all the refrigerators. HOLY JESUS! There are 31 refigerators, not including 4 ice makers. Not all the restaurants have this many, but none I've been to so far have less than 12. Most of the machines at the big place are Traulsens, there are also a few Randells.
I spoke to one of my last instructors from school who told me my best bet was to go to ABCO in Long Island City and get as much info on the machines as possible.
...Also, I need to come up with a list of things that no Service tech can live without on the job. The job has relatively limited tools to supply me with since I am the first guy on the job. But they are willing to get me what I need. They have a vac pump and recovery pump, some new gauges, digital thermometer, some bottles of refrigerant (r404a r134a etc.) They don't have a recovery tank, so I'll have to get a few. I've got screwdrivers, nut drivers, pliers, a decent brush, and a wrench set. Can you guys think of anything else I might need?
Again, let me Thank all of you in advance of your replies... your comments are REALLY appreciated.

Well... on to day three, wish me luck.

[dorrmann]

Definately get a pipe clamp for your thermometer. It will make getting superheat and subcooling readings easy.

The fluke clamp is good, but pricy.

Don't forget a micron gauge as well.

My infrared thermometer is great for box temps.

[rango]

Originally posted by funzrlow
HOLY JESUS! There are 31 refigerators, not including 4 ice makers. Not all the restaurants have this many, but none I've been to so far have less than 12.

Boy are you in for a tret. 3 of us have 35 Mickie D's and can barely keep up with service calls let alone pm's on about 6-8 small boxes, WIC/WIFs and 6-8 RTUs, + ice amchines, then we have to do the other equipment(grills, fryers, etc. Best part is ......always learning. THat's cool.

[rango]

That's for each store , of course.

[gbfromsd]

must have a refrigerant scale, a good one

recovery bottles - I do with 3
One's a working bottle - what goes in it comes right back out. Two's a garbage bottle - I keep filling it with one
gas till I work another gas, then it goes in for reclaim.
The third is a garbage bottle for that other gas. It becomes #2 when #2 goes in for reclaim.

[patchdf1354]

Here's something to ponder. My town has 2300 restaurants. Each let say has 1 ice machine, 1 freezer, 1 walk-in, 2 reach-in, typically 5 to 20 boxes to keep cold. Each unit has maybe 10 items that usually break afters 5 years. so every 5yrs 50 gizmos will go bad in 1 restaurant. 50 divided by 12 months is around 4 things that go bad each month per restaurant. 2300 restaurants one problem per week is 2300 gizmo's per week just in restaurants. Not to mention liquor stores, grocery, rest homes, hotels, bars, topless joints, bakeries, bla bla bla bla bla. The numbers are staggering. The good thing is no one has time to take bids. The health deptment is your friend. So if you really think about it, it isn't really about refrigeration but MARKETING yourself. Putting the fish in the boat is easy, but finding the fish is the money making key to this business. In the summer I can get as many as 15 calls in one day just for me, myself and I. If you can do on AVERAGE 3-8 calls at $125 to $400 per call a day with minimal call backs you'll do soem serious bank. Be cheap on regualars and expensive on the one's that are not in your circle of good customers. Don't put all your focus on refrigeration but 5 to 10% on MARKETING..... It helps to be good at what you do also. You'll learn everyday. Some guys like 1 customer a day and take a 2 hour lunch, and drive 65. To each his own. You'll be frustrated eveyday with something or an other. Good luck and stick to it you'll get there piece by piece...

[Edited by patchdf1354 on 05-26-2004 at 06:00 AM]

[jaypslugger]

I knew a guy that graduated Apex. We hired him as a helper/apprentice. Believe it or not, this guy did not know how to attach his manifold set to an air conditioner! When I asked him how the h*ll he graduated without knowing how to take pressure readings, he shrugged his shoulders. He was a great guy but a bad tech. He ended up driving a UPS truck.

[funzrlow]

Wow, I do feel a little better now. I do infact know how to properly connect my gauges to a unit.
Here's an update for those that even care...
I went in to work yesterday and told the boss that I would require some tools to work on the units the have. Items like a scale, recovery tanks, micron gauges, etc. As I said before, my boss has no real knowledge of Refrigeration. My bosses reply to this was " You don't need some scale to top off my machines". "i've never seen anyone use a scale before". He proceeds to tell me that if I just "top off" the machines that everything will be fine. Then I ask him about the recovery tanks. He then tells me that they are not necessary either.
I had no idea how to respond to this, other than telling him that I probably was not the right guy for this job. I really am not ready to be the only guy maintaining and fixing over 100 refrigerators in their 7 restaurants. I don't want to waste my or his time.
So, I'm on to the next interview today. It's a differant type of job altogether. The interview is for a maintanance person For a group of apartment buildings. Each unit has a heat pump type system. The best part is that there will be somebody there to train me. Anyway, I certainly hope that this position will be a better fit for me.
Thanks again for anyone who gave some helpful tips.

[r22coolguy]

A few other tools to think about:

Refrigerant Scale (you can't charge captubes without one)

Cordless drill (The refrigeration gods just love sheet metal and #8 self-tappers. After you spend some time using a nut driver, you'll invest in a makita or dewalt)

Multimeter (get one that tests compacitors, and might as well include flame rods as well, micro-amps)Fluke 16 or one of the fieldpieces, either the stick DMM or the all-in-one.

Torch set (there are several manufacturers, and everyone has a favorite, turbo torch and uniweld are two, there are more)

Swagging tools, flareing tools, tubing cutters (don't forget a mini, you'll know why one day), fin straightner, service valve wrenchs, schrader core removers.

Look on the wall at your local parts house, alot of the tools are just waycool and you can do without them, but some of the specialty items come in handy. Buy a little at a time and build your arsenal. I hate to be elbow deep and need something and have to stop what I'm doing and head clear across town to get it.

If ritchie makes it, you need it God I love yellowjacket.

[baltazar]

hey cobitech, since i only in resenditiol work, i found your answer intriging about 10,20,30, method but what about head temp whats the method for that , i like you answers, and the way discribethem.

[cobitech]

Baltazar,

To find the head pressure add the ambient(surrounding air temp) to 30°-35°.

example: 90°ambient + 35° = 125°=275psig (R-22)Pressure temp chart. 200psig to 300psig range is what you are looking for.

always check discharge line temperature for overheating (225° is the maximum temp that should be measured 6" from compressor.